Xfinity XB8 Router/Modem Login

Comcast technician came in today and replaced my defective XB7 router with a new XB8 router. Technician installed and activated the XB8.

I'm trying to sign in into the XB8 router to set some parameters. I'm using the admin as username and the password on the XB8 router and states incorrect password.  I then use the username and password from the old XB7 router and get the same message.

How to I login into the XB8 router?I do not want to do a factory reset.